

Sectional Analysis of Cross-Laminated Timber as a Design for Fire Methodology
Abstract
Current European structural fire design methodology for cross-laminated timber (CLT) elements predominantly uses a reduced cross-section method, which fails to realistically capture the variation of mechanical properties of timber at elevated temperature or with variable grain directions. A thermomechanical sectional analysis, compared against fire tests on CLT slab strips is presented herein, using two different sets of temperature-dependent mechanical properties available in the literature. This is investigated as an alternative, more rational design approach for CLT flexural elements exposed to fire. Initial results show reasonable correlation with experimentally observed failure times (i.e. fire resistances). Both failure time and deflection response are shown to depend on the temperature-dependent mechanical properties of timber used as modelling inputs, and the recommended properties presented in the Eurocode may not be suitable on the basis of the testing and analysis presented. Further research is needed to corroborate this conclusion